Fluid-operated motor



2 SHEETS SHEEI l.

Patented Dec; 6,

Ml M m N m: MN- %H\ SWAN \N k v W N m w in I r allll (T R II W UNITEDSTATES PATENT OFFICE.

GUSTAVE M. NELL, OF DENVER, CC JLORAI JO, ASSIGNOR TO THE DENVER ROCK DRILL MANUFACTURING COMPANY, OF DENVER, COLORADO, A CQRPORATION OF DELA-WARE.

Application filed March 29, 1918.

To all whom it may concern:

Be it known that I, GUSTAVE M. NELL, a citizen of the United-States,residing at Denver, in the county of Denver and State of Colorado, haveinvented certain new and useful Improvements in Fluid-Operated Motors,of which the following is a specification.

The present invention relates to so-called pneumatic hammers in which anexpansive motive fluid is utilized for. operating a piston.

The object is toprovide'a. novel structure of'a simple character that ishighly effective for distributing motive fluid to the piston to actuateit, and permitting a free exhaust therefrom, at the same time obtaininga cushion to the piston at the limit of its stroke.

An embodiment that is at present considered preferable, is illustratedin the accompanying drawings, wherein Figure 1 is a plan view of thetool,

Fig. 2 is a longitudinal sectional vlew therethrough,

' Fig. 3 is a front elevation, and

Fig. 4: is a cross section on the line l4 of F i 2.

bimilar reference numerals designate corresponding parts in all thefigures of the drawings.

In the embodiment disclosed, a cylinder member is employed comprising'abarrel 5 closed by a front head 6 and a rear head 7 The head 6 is formedwith a suitable chuck 8 to receive a tool, as a drill steel, a portionof which is shown at 9. Therear head 7 is provided with a suitablehandle 10, and the cylinder member'formed by the barrel and heads ismaintained in assembled condition by side bolts 11 connecting the headsand clamping them firmly against the ends of the barrel 5, as willbe'evident. The cylinder member is formed with a piston chamber 12, tothe ends of which motive fluid is supplied through a channel 13 havingports 14 opening into the ends of'said chamber, and preferably incommunication with annular grooves 15 formed therein. Exhaust ports 16open into the chamber at the ends thereof and just inside the groove 15,these ports also communicating with suitable grooves 17. A third exhaustport 18 opens into the piston chamber midway between the port 16, and isSpecification of Letters Patent.

FLUID-OPERATED MOTOR.

Patented Dec. 6, 1921.

Serial No. 225,511.

also preferably. in communication with an annular groove 19. g Areciprocatory sleeve valve 20 is located in the piston chamber and isprovided with reduced ends 21 that form internal 0ppo- 'sitely facedpressure shoulders 22. These reduced ends are received alternately byannular pockets 23 formed by reducing the heads 6 and 'K "at their innerends and where they enter the ends of the'barrel. Ports 24 open from thesupply ports 14' into said pockets. The sleeve valve is furthermorevprovided midway of its ends with an exhaust port 25 that is in constantcommunication' withthe exhaust port 18 of the barrel, v

and said sleeve valve has end exhaust ports 26 that are respectivelymovable into and out of communication with the exhaust ports 16,accordingly as the valve is shifted;

A reciprocatory piston is employed which includes a head'27 operating inthe sleeve valve 20 with a forwardly extending hammer portion'28 adaptedto strike against the rear end ofthe tool 9. 'This. piston also has are'arwa rdly projecting bosst29 adapted to enter a correspondingrecess30 formed in the rear head 7.

Briefly-described; the operation is follows: With the parts as'shown inFig. 2 the piston has completed its forward stroke, and the sleeve valve20 has been moved .rearwardly;- In this position, the foremost supplyport 14 is uncovered, while the rearmost su'pply'port is covered by therear end of the valve. Motive fluid therefore will enter the front endof the piston chamber and drive the'piston rearwardly, the exhausttaking place through the ports 2518' and 2616.

As soon as the piston head 27 covers the rear exhaust port 26, it willbe evident that motive fluid'will be trapped behind the pistonand'the'pressure will rise. This not only constitutes'a cushion, butzalso causes additional pressure against the rear internal shoulder 22of'the valve, overbalancing the exhaust port 16. The ports 25 and 18remain in communication, and will now be in front of the piston head. Aforward movement of the piston will thereupon take place until the frontlimit of its strokeis reached, whereupon a rearward shifting of thevalve will occur and the cycle of operations thus will be continued. Theports 24 are employed for balancingthe pressure against the reducedends, insuring the proper action of.

the valve.

From the foregoing, it is thought that the construction, operation andmany advantages of the herein described invention will be apparent tothose skilled in the art, without further description, and it will beunderstood that various changes in the size, shape, proportion and minordetails of construction, may be resorted to without departing from thespirit or sacrificing any of the advantages of the invention.

. Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is I 1. In apparatus of thecharacter set forth, the combination with a cylinder member, of acontinuous sleeve valve movably mounted within the cylinder member, apiston reciprocating in the cylinder member, means controlled by thesleeve valve for supplying motive fluid to the piston for actuating it,means for maintaining pressure in opposite directions against the valve,and means controlledby the piston on its movement for increasing thefluid pressure alternately in opposite directions against the valve toshift the same. a

2. In apparatus of the character set forth, the combination with acylinder member, of an open ended continuous sleeve valve movablymounted in the cylinder member, pockets in the cylinder member foralternately .receivingthe ends of-the valve, a piston. reciprocating inthe cylinder member, means controlled by the sleeve valve for supplyingmotive fluid to the piston for actuating it, and means controlled by thepiston on its movement for increasing the fluid pressure alternately inopposite directions against portions of the valve outside the pockets toshift the same.

3. In apparatus of the character set forth, the combination with acylinder member, of an open ended sleevevalve movably mounted in thecylinder member, pockets in the cylinder member for alternatelyreceiving the ends of the valve, said valve having op positely disposedinternal pressure surfaces contiguous to said ends, a pistonreciproeating in the cylinder member, means for supplying motive fluid.to the pockets, means controlled by the sleeve valve for supplyingmotive fluid to the piston for actuating it, and means controlled by thepiston on its movement for increasingthe fluid pressure forming aninternal shoulder, an annular pocket in the cylinder member to receivethe reduced end, means for maintaining fluid.

under pressure in the pockets, a piston operating in the sleeve valve,means controlled by the sleeve valve for supplying motive fluid to thepiston to actuate the same, and means providing .an exhaust through thesleeve valve behind the shoulder, whereby the piston traps motive fluidand produces an increased pressure against said shoulder when the pistonpasses the exhaust permitting means to shift said valve.

5. In apparatus of the character set forth, the combination with acylinder member having a piston chamber, of means for supplying motivefluid to the ends of the piston chamber, a continuous reciprocatorysleeve valve operating in the piston chamber and movable across thesupply means, said sleeve valve having reduced ends forming oppositelydisposed internal pressure shoulders, pockets in the ends of thecylinder member for receiving the reduced ends, said cylinder memberhaving ports for maintaining pressure against the ends of the sleevevalve when in the pockets, a reciprocatory piston operating inthe-sleeve valve, and means for permitting exhaust from opposite sidesof the piston, including ports in the end portions of the sleeve valve,the piston passing said ports and building up pressure against theinternal shoulders for effecting the shifting of the valve.

6. In apparatus of the character set forth, the combination with acylinder member, of a sleeve valve therein having an intermediateexhaust port and exhaust ports near its ends, a piston operating in thesleeve valve and traversing the intermediate port to permit exhausttherethrough from opposite sides of said piston, exhaust permittingmeans with which the end ports alternately communicate upon the shiftingof the valve, and means controlled by the operation of the pistontoshift the valve. 7 a

7 In apparatus of the character set forth, the combination with acylinder member having a spaced terminal and anintermediate exhaustpermitting means, of a sleeve valve therein having an intermediateexhaust port in constant communication with the intermediate means ofthe cylinder member,and end exhaust ports respectively movable into andout of communication with the end exhaust permitting means of thecylinder member, a piston operating in the sleeve valve and traversingthe intermediate port thereof to permit exhaust through said port fromopposite sides of said piston, means fluid to the piston to actuate it,and means mediate exhaust port in constant communicontrolled by thevalve for supplying motivelsleeve valve furthermore having anintercontrolled by the operation of the piston to cation with theintermediate port of the cyll inder member, and a reciprocatory pistonin shift the valve.

8. In apparatus of the character set forth the combination with acylinder member having a piston chamber and motive fluid supply portsopening into the ends of the same, said cylinder member furthermorehaving an exhaust port opening into the ends of the piston chamber and aport between the end ports also opening into said piston chamber, areciprocatory sleeve valve in the piston chamber having oppositelydisposed pressure surfaces at its ends, said sleeve valve operatingacross the supply ports and having end exhaust ports movable into andout of communication with the exhaust ports of the cylinder member, the

the sleeve valve movable across the intermediate exhaust port thereof topermit the exhaust therethrough from opposite sides of the piston, saidpiston also covering and uncovering the end exhaust ports and therebybuilding up pressure against the pressure surfaces of the sleeve valv tomove the same in opposite directions.

In testimony whereof, I afiix my signature in the presence of twoWitnesses.

GUSTAVE M. NELL.

Witnesses:

ALICE M. J ONES, SULLIVAN JOHNSON.

